Instructions
Turn on your PS3 console and navigate to the "PlayStation Network" icon in the far-right side of the XML menu bar.
Scroll down and select the "PlayStation Store" icon, which looks like a shopping bag. Press "X" on your PlayStation controller to select the icon.
Sign in using your Sign-In ID (email address) and password. Press the "Sign In" button to access your PlayStation 3 Store account.
Scroll down to the bottom of the left toolbar and select the "Themes &Avatar" option. You will see a list of different themes from which to choose.
Browse through the pages of themes until you find the one you want to download. Click on the thumbnail of the theme to receive a detailed description and the options to "Buy Now" or "Add to Cart." If you are purchasing other themes, click the "Add to Cart" button. If you are only purchasing one theme, click the "Buy Now" button to continue to the checkout process.
Review your theme purchase on the next page and click on the "Confirm Purchase" button. You must have a credit card on file with the PlayStation Network in order to make the purchase.
Download the theme after you purchase it by clicking on the "View Downloads" icon in the top-left corner in your PlayStation Store account page. You will see a list of purchased items.
Find the theme you want to download and press the "X" button on your PS3 controller to complete the download process.